ABC News(WASHINGTON) -- The United States is now providing manned intelligence, surveillance and reconnaissance flights over Nigeria and sharing commercial satellite imagery to aid in the search for nearly 300 missing schoolgirls, a senior administration official said Monday.

This help is in addition to 27 U.S. officials who are either on the ground or en route to Nigeria to help find the students, captured by the terrorist group Boko Haram.

The new assistance has been approved by the Nigerian government to aid in the search.

Secretary of Defense Chuck Hagel told ABC's Martha Raddatz Sunday that the U.S. would not be sending American troops to help with the search effort.

"There's no intention, at this point, to be putting any American boots on the ground there," Hagel said on ABC's This Week.